Propeller electrical connector system



Feb. 17, 1953 E. w RADTKE ET AL 2,628,794

PROPELLER ELECTRICAL CONNECTQR SYSTEM Filed May 26, 1950 6 Sheets-Sheet l Fig. I.

1w veuio 7'; Edward M. Raike L2! Q/IgeuZ Feb. 17, 1953 E. w. RADTKE ET AL 2,628,794

PROPELLER ELECTRICAL CONNECTOR SYSTEM Filed May 26, 1950 6 Sheets-Sheet 2 Feb. 17, 1953 E. w. RADTKE ETAL 2,628,794

PROPELLER ELECTRICAL CONNECTOR SYSTEM Filed May 26, 1950 6 Sheets-Sheet 5 Fayi. 40

0,, W FWIAM Feb. 17, 1953 w, RADTKE 1 AL 2,628,794

' PROPELLER ELECTRICAL CONNECTOR SYSTEM Filed May 26, 1950 v e Sheets-Sheet 5 2 M FWJAM Feb; 17, 1953 v E. w. RADTKE ETAL 2,628,794

PROPELLER ELECTRICAL CONNECTOR SYSTEM 7 Filed May 26, 1950 s Sheets-Sheet e Patented Feb. 17, 1953 sternum ELECTRICAL QON GIOB sY EM Edward Radtke, Manchester, and Wilh'am .E. Dieienderfcr, Wethersficld, Conn assignors .t limi ed Airc aft Corporation, East Ha tford Conn a corporation of Delaware Application May '26, 1950 Serial N9. 164,412

drive shaft, the control housing having elements thereof -operativel-y connected to the rotatable propeller portion.

A further object of this invention 'to provide a propeller installation comprising a hub unit, a control unitoperativelyconnected thereto and mechanism for transmitting-electrical power from the engine to the control .andzhub units includingstop means for fixing the control unit against rotation upon assembly of the propeller cnthe engine drive shaft.

Another object ofthis invention isto provide an improved propeller mechanism which can :be

installed with greatfacility without the necessity .of making numerous manual connections for the electrical circuits :or control unit stop. This is particularly advantageous in propellers having enclosing spinners.

These and other objects will become readily apparent from the following detail description .of the drawings in which:

Fig. lis a side elevation of the propeller in mounted position.

Fig. 2 is an enlarged View in partial cross.- section illustrating the electrical connector -or adaptor of this invention.

Figs. '3 and .4 are opposing side views taken along the lines 3+3 ands-+4, respectively, of Fig. .2.

Fig. 5 is an illustration of the inboard side of the propeller control-uniti. -e., a-view looking outboard from the engine nose.

Fig.6 is a schematic and cross-sectional illustration of the electrical .connecting --systemv ith --the .crossrsection portion of the figure being a composite of cross-sections taken along the lines tee-6 of 'Fig. 2' and.6ce-:Ec of Fig. 5. This figure illustrates the assembled positionlof the electrical connecting mechanism.

Fig. '7 is a partial cross-sectionsimilarto-Fig.l

2 illustrating the'hubtcarried electrical connections including a schematic showing of the blade deic- .ing elements.

Fig-3 is a partial view of theoutboard or nose 5 end of the propeller.

Referring to Fig. 11, a propeller assembly is shown comprising ahub 20, acontrol'unit :24 and an electrical adaptor 26 with .the entire assembly being mounted in position .on an engine 30 illustrated partially in phantom which engine by means of its shaft 32 drives .the hub portion at of the propeller.

The hub 28 carries a plurality of blades 36 mounted for pitch changing movement relative thereto. Thepitchcf-thebladesdlimay be varied 'by any :number of wellr'known means as for example by-hydraulicpitch,changingmotcrs carried Within the rbaserof each of the blades.

The control .unit :24 comprises a housing 38 which 'bothrcarries and encloses various pitch c nt ol m c a isms whi h .fo ur s s o t ldescr n ion'nee no rlo dealt w h detail. It

. .howev t. t indicate that a s eed n t B m ar soontrollinsImprements t car at mech ni m w thin t ou in WhiQ fi. i 'QQI ZQ l Si rot t on of t se i? and sworn 3!? not 4 car ied t n e no at 1 n .1 tom imparts reciprocating mo on to an element 46 3o wliioh oo tfol a di t ibuto :va o lfio fiii si i 1 co ve i nc o di ect n fluid u e p s re to e itc ohan ngmotbrs t ac n l a y the oho the .l lad s flu d undo r ssure may be provided by one or more pumps arr ed Pl th 1 2. and dr v n ia a ea 148 b um dri gea oats-noting Wit th hub and ha ing an oserat re co nect to e con l o itii; flh um l ssc'ar 5 many remain s ationary sotoe t ioho ca pumps ar n lmal y e a a lts iilt prope ler ot lo An auxi iary n to ioi car i by t con r u i op r ion conn ct d to the um d ive gear fi il so that the hub carried pumps may be driven when thepropelleris stationary'lby rotati-ngthenormally stationary gear tid' {The entire control unit mechanism and the pitch changing mechanism carried by the huh are described in detailin copending patent Application Serial -Nc. 159;736, filednayegiosa-ty Melvin state"- :In order to provide electrical power or the iverious electrically respon siye units which have been described and are to be described, the adaptor 26 is provided and is fixed to the engine 33 by means of bolts 60. As seen in Figs. 2, 3 and e, the adaptor 26 comprises a semi-circular bracket 64 which supports the adaptor on the nose of the engine and carries threaded type electrical couplings 66 and 58 which are adapted to receive cooperating couplings leading to conduits carried by the engine and fixed aircraft structure. The adaptor 25 further includes an extending portion 10 which protrudes in an outboard direction toward the propeller and is composed of a plurality of spring loaded contact plungers i2 and iii which are adapted to engage cooperating contact points carried by the control unit 24. The extending portion 10 forms a wall which surrounds the contacts 12 and 14 and has fixed thereto a resilient seal 18 adapted to engage a cooperating cup-like extension 89 (Fig. 5) which protrudes in an aft direction from the rear side of the control unit 2%.

Referring to Fig. 5, the control unit 24 carries a plurality of contact points 84 and 86 which cooperate with the contact plungers 12 and 14, respectively, carried by the adaptor 26. The contacts 84 conduct electricity to the various electrical elements of the servo control unit 40 and a pitch limit switch unit 08 as well as a reversing solenoid (not shown). The servo control unit includes a controlling proportional solenoid (not shown) which responds to a signal from the propeller governor. The detail electrical system for these various units is described in the abovementioned co-pending patent application. At least one of the contacts 85 provides an electric connection by means of a conduit 90 to the auxiliary motor 54.

The extending portion 10 of the adaptor 26 and the cooperating cup-like portion 60 carried by the control unit 24 are more clearly illustrated in their assembled position by referring to Fig. 6. As herein illustrated, it can be seen that the extending portion 10 protrudes within the confines of the Wall I00 of the cup-like portion 80 so that the contact plungers 12 engage the contacts 84 and the plungers 14 engage the contacts 86 While at the same time the seal 18 engages the wall I65 to prevent moisture or dirt from entering and accumulating on the electrical contacts.

The particular leads from the aircraft to the adaptor 26 are illustrated schematically in Fig. 6 so that detail description thereof is not necessary.

It is apparent that the extending portion 155 on the adaptor 26 forms a male stop which cooperates with the wall I00 so as to position the control unit casing while also serving to hold the latter against rotation when the hub is driven by the engine. As a result upon installing the hub and control unit combination on the engine drive shaft the necessary electrical connections are automatically engaged while the control unit housing is simultaneously positioned and held against rotation since the latter is freely mounted relative to the drive shaft 32. However, it will be, noted that a source. of power or battery H0 is provided which has electrical connections to the electronic governor, the manual pitch controls, deicer control and auxiliary motor control each of which are carried by fixed aircraft structure. The tachometer generator is driven by the engine and feeds a variable voltage to the governor consistent with engine speed so that in turn the electronic governor passes a governing signal to the previously mentioned proportional solenoid and servo control (carried by the control unit 4 24) via the electrical connections through the adapter 26 and to the control housing 38.

Similarly, the auxiliary motor control can furnish electrical power via the line II6 to the contact plunger H8 and eventually to the conduit 00 (better seen in Fig. 5). The deicer control in turn provides electrical power via leads I22 and I24 to contact plungers I26 and I28 each of which are connected to a bus bar I30. For purposes to be described hereinafter, two bus bars are utilized for transmitting power to a plurality of brushes I34, groups of which contact slip rings carried by the propeller hub 28. Each slip ring has a number of brushes contacting it so that a high current load can be passed to the slip ring without necessarily utilizing a prohibitively large single brush.

The deicing power brushes I34 are better seen in Fig. '1 and for convenience are referred to as brushes I40, I42 and I44. As previously described, the control unit 24 is held stationary hence the brushes I40, I42 and I44 will also be stationary relative to .the hub 20. Thus, slip rings I50, I52 and I54 are carried by the rotatable hub to conduct the current from the brushes I40, I42 and I44. The reason three brushes are utilized herein is that one of the brushes acts as a common ground return back to fixed aircraft structure while each of the other two brushes provides current for the deicing elements of two of the blades of the four-blade construction illustrated. The deicing elements of two blades only are energized at any one time in an intermittent manner so that the load on the aircraft electrical system will not be excessive at any one time. Each of the slip rings, taking for example the slip ring I50, has a bolt type electrical connection I60 to a spring type jumper I62 which engages one of the posts I64, I66 or I68. Assuming for the time being that current is being supplied to the post I66, current will flow via the line I10 to the brush I12 into the semi-circular slip ring I14 from which current is fed to the deicer element I16 and back again to a cooperating semicircular slip ring I 18. The semi-circular slip rings I14 and I18 form a cooperatin pair separated by insulation I so that they surround the shank of the propeller blade 34. Current is subsequently fed from the slip ring I18 to the brush W4 and to a lead I86 which, as better seen in Fig. 8 connects with the opposite blade and permits current to flow to a brush I88 (Fig. 1), slip ring I90 and the deicing element I92 carried by such opposite blade. Current will then flow to the slip ring portion I94, through the brush I96 and back to the post I68 which will return the current to the common ground. It will be noted that the electrical path just described comprises a series connection between the deicing elements of opposite blades which insures simultaneous deicing of such blades to prevent anyblade unbalance. Thus, if a deicing element of any one blade should become inoperative, current will be cut oil automatically to the deicing element of the opposite blade.

It will be apparent that as a result of this invention a simple yet positive means of providing electrical connection for propellers is provided whereby the entire propeller and its control unit may be assembled separately and upon installation of the propeller on the engine all the necessary electrical connections will be automatically engaged while also the control unit will be positioned and held stationary during subsequent propeller, operation.

Although only one embodiment of this invent tion has been illustrated and described herein, it will be apparent that various changes and modifications may be made in the construction and arrangement of the various parts without departing from the scope of this novel concept.

What it is desired to obtain by Letters Patent is:

1. In an aircraft, engine including a propeller shaft, a source of electrical power fixed relative to said engine, an adaptor fixed to said engine adjacent said shaft including a plurality of electrical contacts operatively connected to said source of power, an abutment carried by said adaptor, a propeller assembly comprising a rotatable hub driven by said shaft and a control unit operatively connected thereto, said control unit comprising, a housing movable relative to said hub, and a stop carried by said housing, electrically responsive elements carried by said propeller assembly, and a plurality of members engageable with said contacts upon assembly of said propeller assembly on said shaft whereby said stop engages said abutment to fix said housing relative to said engine.

2. In an aircraft, the combination of, an engine including a propeller shaft, a source of electrical power including electrical connectors leading therefrom, an adaptor fixed relative to said engine having an operative engagement with said connectors including a pluralityof electricalcontacts, abutment means carried by said adaptor, a propeller control unit freely mounted relative to said shaft adapted to receive said electrical contacts including stop means cooperating with said abutment means whereby said control unit is held stationary during propeller rotation, multiple electrical elements carried by said control unit, apropeller hub mounted on said shaft and having a plurality of variable pitch blades carried thereby including electrically responsive elements, and means carried by said hub operatively engaging said electrical elements when said hub is in its assembled position on said shaft.

3. In a combination according to claim 2 wherein said electrically responsive elements include deicing means carried by said blades and having a continuous electrical connection with the engaging means carried by said hub.

4. In a combination according to claim 3 wherein the electrical connection between said blade deicing means and said hub comprises a brush and slip ring combination, and the engaging means carried by said hub comprises slip ring mechanism engageable with said multiple electrical elements.

5. In an aircraft, the combination of, an engine for the aircraft including a propeller shaft, a source of electrical power carried by the aircraft including connections to said engine, a propeller assembly having a control unit forming an operative part thereof and including electrically operated control mechanism carried thereby, stop means carried by said control unit for holding said unit stationary relative to the engine when the propeller is rotating, a removable electrical connector unit adapted to be fixed to the engine, multiple electrical connector means carried by said connector unit, and cooperating electrical connector means carried by said propeller control unit and adapted to receive said multiple connector means when the propeller is assembled on the engine shaft thereby providing a through connection between said propeller carried control unit and said electrical supply source, said removable connector unit including cooperating 3 abutment means thereon engaging said stop me ns for hq ti ning said control unitwith respect to said engine upon assembly of said propeller on said shaft.

6. In an'aircraft comprising an engine and a propeller drive shaft, a source of power including operative connections to said engine, manual control means fixed relative to said engine, a removable electrical adaptor fixed relative to the engine having operative connections to said source cf'power and said control means including, a stop and a plurality of electrical conductors, a control unit surrounding said drive shaft and having abutment means cooperating with said stop whereby said control unit is fixed against rotation relative to the power plant, said unit comprising electrically operated units, electrical conduits and means for interconnecting said conduits with said electrical conductors upon assembly of said control unit over said shaft and adjacent said engine, a rotatable hub adapted to be mounted on said shaft including electrical mechanism carried thereby, and electrical transfer means carried by said hub and operatively engageable with said electrical conduits thereby providing an electrical path to said rotatable hub.

7. In an aircraft, an engine including a propeller shaft, a propeller adapted to be driven by said shaft comprising, a hub surrounding said shaft and having variable pitch blades carried thereby, and a control unit inboard of said hub and having operative connections to said hub, said control unit including an annular casing surrounding said shaft and adapted to be r0- tatable relative to said hub, electrically responsive elements carried by said hub, means providing an electrical path from said unit to said hub comprising cooperating slip rings and brushes, a source of power fixed relative to said engine, an adaptor fixed relative to said engine comprising operative connections to said source of power, a plurality of spring loaded electrical contacts, and a flange depending from said adaptor in an outboard direction and surrounding said contacts, electrical means carried by said unit engageable with said contacts, a cup-shaped stop carried by said unit and surrounding said electrical means, said cup-shaped stop protruding axially of said shaft in an inboard. direction whereby said stop engages said flange and said electrical means engages said contacts upon assembly of said propeller on said shaft.

8. In an aircraft, an engine including a propeller shaft, 3, source of power fixed relative to said engine, an adapter fixed to said engine adjacent said shaft including connectors operatively connected to said source of power, an abutment fixed relative to said adapter, a propeller assembly comprising a rotatabl hub driven by said shaft and a control unit operatively connected thereto, said control unit comprising, a housing movable relative to said hub, and a stop carried by said housing, power responsive elements carried by said propellerassembly, and means engageable with said connectors upon assembly of said propeller assembly on said shaft whereby said stop engages said abutment to fix said housing relative to said engine and operatively connect said power responsive elements to said source.

EDWARD W. RADTKE. WILLIAM E. DIEFENDERFER.

(References on following page) Number The following references are of record in the 2,444,557

file of this patent: 3 232 523 UNITED STATES PATENTS 5 2,499,825

Number Name Date 2,502,307

1,737,912 Bogard Dec. 3, 1929 2,523,905

1,807,359 Waters 1 May 26, 1931 1,951,320 Blanchard Mar. 13, 1934 2,245,251 Chilton June 10, 1941 10 2,377,386 Stalker June 5, 1945 2,402,770 Poekel June 25, 1946 2,429,061 Hunter Oct. 14, 1947 13 relied o 7 V REFERENCES CITED Name Date Eaton July 6, 1948 Hoof Apr. 5, 1949 Martin Jan. 17, 1950 Havlicek Mar. 7, 1950 Bascom Mar. 28, 1950 Hellen Sept. 26, 1950 OTHER REFERENCES Hydromatic Propellers Electric De-Icing Systern," published 1947 by Hamilton Standard Propellers, Service Publications Section, pp. 5, 10 and (Copy in Division 22.) 

